Simplified sleep restriction for insomnia in general practice: a randomised controlled trial.

BACKGROUND: Insomnia is common in primary care. Cognitive behavioural therapy for insomnia (CBT-I) is effective but requires more time than is available in the general practice consultation. Sleep restriction is one behavioural component of CBT-I.

AIM: To assess whether simplified sleep restriction (SSR) can be effective in improving sleep in primary insomnia.

DESIGN AND SETTING: Randomised controlled trial of patients in urban general practice settings in Auckland, New Zealand.

METHOD: Adults with persistent primary insomnia and no mental health or significant comorbidity were eligible. Intervention patients received SSR instructions and sleep hygiene advice. Control patients received sleep hygiene advice alone. Primary outcomes included change in sleep quality at 6 months measured by the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and sleep efficiency (SE%). The proportion of participants reaching a predefined 'insomnia remission' treatment response was calculated.

RESULTS: Ninety-seven patients were randomised and 94 (97%) completed the study. At 6-month follow-up, SSR participants had improved PSQI scores (6.2 versus 8.4, P<0.001), ISI scores (8.6 versus 11.1, P = 0.001), actigraphy-assessed SE% (difference 2.2%, P = 0.006), and reduced fatigue (difference -2.3 units, P = 0.04), compared with controls. SSR produced higher rates of treatment response (67% [28 out of 42] versus 41% [20 out of 49]); number needed to treat = 4 (95% CI = 2.0 to 19.0). Controlling for age, sex, and severity of insomnia, the adjusted odds ratio for insomnia remission was 2.7 (95% CI = 1.1 to 6.5). There were no significant differences in other outcomes or adverse effects.

CONCLUSION: SSR is an effective brief intervention in adults with primary insomnia and no comorbidities, suitable for use in general practice.